Imaging individual vacancies in solids and revealing their interactions with solute atoms remains one of the frontiers in microscopy and microanalysis. Here we study a creep-deformed binary Ni-2 at.% Ta alloy. Atom probe tomography reveals a random distribution of Ta. Field ion microscopy, with contrast interpretation supported by density-functional theory and time-of-flight mass spectrometry, evidences a positive correlation of tantalum with vacancies. Our results support solute-vacancy binding, which explains improvement in creep resistance of Ta-containing Ni-based superalloys and helps guide future material design strategies.
@article{arxiv.2103.01639,
title = {Revealing atomic-scale vacancy-solute interaction in nickel},
author = {Felipe F. Morgado and Shyam Katnagallu and Christoph Freysoldt and Benjamin Klaes and François Vurpillot and Jörg Neugebauer and Dierk Raabe and Steffen Neumeier and Baptiste Gault and Leigh T. Stephenson},
journal= {arXiv preprint arXiv:2103.01639},
year = {2021}
}